Laboratory for Molecular Diagnostics
Center for Nephrology and Metabolic Disorders

lipoprotein lipase

The protein product, an intravascular enzyme, degrades very low density lipoproteins and chylomicrons. A deficiency in this enzyme activity results in chylomicronaemia or hypertriglyceridaemia.

Epidemiology

The frequency of homozygous LPL deficiencies is 1:1,000,000.

Gene Structure

The size of LPL gene is about 30kb. This gene is located on chromosome 8 (8p22). The gene has 10 exons.

Phenotype

The clinical signs of lipoprotein lipase deficiency and apolipoprotein C2 defects are identical. Biochemically a hyperlipoproteinemia type I can be considered in homozygous state. In heterozygous state there is rather a mixed hyperlipidemia evident. That can be type V according to classification of Fredrickson. There is often recurrent pancreatitis seen in these patients. The skin may show xanthomas.

Pathology

The l Lipoproteinlipase is a glycosylated enzyme. It is produced by adipocytes and secreted into blood stream. Its function is lipolytic degradation of triglycerides in triglyceride rich lipoproteins. The important cofactor on these lipoproteins is Apolipoprotein C2.

Test Strategy

Patients with excessive triglyceridemia and/or recurrent pancreatitis.

Interpretation

This test is appropriate to confirm lipoprotein lipase deficiency. This is much more easily to perform than direct measurement in plasma. In combination with apolipoprotein C2 testing it is even a much more reliable test for insufficient lipoprotein degradation. The patients have to be treated with a strong regiment of fat free diet.

Genetests:

Clinic Method Carrier testing
Turnaround 5 days
Specimen type genomic DNA
Clinic Method Massive parallel sequencing
Turnaround 25 days
Specimen type genomic DNA
Clinic Method Genomic sequencing of the entire coding region
Turnaround 20 days
Specimen type genomic DNA
Clinic Method Multiplex Ligation-Dependent Probe Amplification
Turnaround 20 days
Specimen type genomic DNA

Related Diseases:

Familial combined Hyperlipemia
Combined familial hyperlipidemia with VLDL overproduction
APOE
GCKR
OSBPL10
USF1
Combined familial hyperlipidemia with adipose tissue dysfunction
C5AR2
CREB3L3
LEPR
LIPE
PNPLA2
PPARG
USF1
Combined familial hyperlipidemia with dysfunctional LDL clearance
ATF6
LDLR
PCSK9
Combined familial hyperlipidemia with dysfunctional VLDL metabolism
ANGPTL8
APOA1
APOA4
APOA5
APOC3
CETP
GALNT2
LCAT
LIPC
LIPG
LPL
RXRG
USF1
Chylomicronemia
APOA5
APOC2
APOE
GPIHBP1
LPL
Combined familial hyperlipidemia with dysfunctional VLDL metabolism
ANGPTL8
APOA1
APOA4
APOA5
APOC3
CETP
GALNT2
LCAT
LIPC
LIPG
LPL
RXRG
USF1

References:

1.

Benlian P et al. (1996) Premature atherosclerosis in patients with familial chylomicronemia caused by mutations in the lipoprotein lipase gene.

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2.

None (1999) Drug treatment of lipid disorders.

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3.

NCBI article

NCBI 4023 [^]
4.

OMIM.ORG article

Omim 609708 [^]
5.

Orphanet article

Orphanet ID 123112 [^]
6.

Wikipedia article

Wikipedia EN (Lipoprotein_lipase) [^]
Update: April 29, 2019